FIG. 6 conceptually shows a method for manufacturing an optical display device mounted on a conventional liquid crystal display device. First, an optical film maker produces a long (band-shaped) sheet material having an optical film as a material roll (#1). A specific step of manufacturing this is a known manufacturing step, so that the description will be omitted. As the material roll of this long (band-shaped) sheet material, there are, for example, a polarizing plate material roll, a retardation plate material roll, a lamination film material roll of a polarizing plate and a retardation plate, and the like used in a liquid crystal display device. Subsequently, the
material roll is slit into a predetermined size (size according to the size of the optical display unit) (#2). Next, the slit long material roll is cut into a predetermined length in accordance with the size of the optical display unit to be bonded (#3). Next, the pieces of sheet materials (optical film) cut into a predetermined length are subjected to inspection of outer appearance (#4). This inspection method may be, for example, a defect inspection by eye observation or an inspection using a known defect inspection apparatus. The defect means, for example, contamination on the surface or in the inside, scratches, a special defect (which may be referred to as a knick) like a twist of a hit trace shape that has bitten a contaminant, an air bubble, a contaminant, or the like. Next, a finished product inspection is carried out (#5). The finished product inspection is an inspection that accords to a stricter quality standard of non-defective product determination than that of an outer appearance inspection. Next, the four end surfaces of the pieces of sheet materials are subjected to end surface processing (#6). This is carried out for preventing a pressure-sensitive adhesive or the like from extending out from the end surfaces during the transportation. Next, in a clean room environment, the pieces of sheet materials are subjected to clean packaging (#7). Next, packaging is carried out for transportation (transport packaging) (#8). In the above manner, pieces of sheet materials are manufactured and transported to an optical display device processing manufacturer.
In the optical display device processing manufacturer, the transported pieces of sheet materials are subjected to unpacking (#11). Next, an outer appearance inspection is carried out for inspecting the scratches, contamination, or the like that has been generated during the transportation or at the time of unpacking (#12). The pieces of sheet materials determined to be non-defective by the inspection are conveyed to a next step. Here, there are cases in which this outer appearance inspection is omitted. An optical display unit (for example, a glass substrate unit having a liquid crystal cell enclosed therein) to which a piece of sheet material is to be bonded is manufactured in advance, and the optical display unit is cleaned before the bonding step (#13).
The piece of sheet material and the optical display unit are bonded (#14). A release film is peeled off from the piece of sheet material while leaving the pressure-sensitive adhesive layer, and the resultant is bonded to one surface of the optical display unit with the pressure-sensitive adhesive layer serving as a bonding surface. Further, a piece of sheet material can also be bonded to the other surface of the optical display unit. In the case of bonding onto both surfaces, either optical films having the same configuration or optical films having different configurations may be bonded to respective surfaces of the optical display unit. Next, inspection of the optical display device in a state in which the optical films are bonded and a defect inspection are carried out (#15). The optical display device determined to be non-defective in this inspection is transported to a mounting process (#16). On the other hand, the optical display device determined to be defective is subjected to a reworking process (#17). In the reworking process, the optical film is peeled off from the optical display unit. Onto the optical display unit having been subjected to the reworking process, an optical film is newly bonded (#14).
In the above manufacturing step, in particular, end surface processing, packaging of the pieces of sheet materials, unpacking, and the like are needed steps because the optical film maker and the optical display device processing manufacturer are located at different places. However, there is a problem of increase in the manufacturing costs caused by multiple steps. Also, there are a problem of scratches, dusts, contamination, or the like generated by the multiple steps or transportation, the necessity of an inspection step accompanying this, and further a problem in that other kinds of pieces of sheet materials need to be stored and managed as a stock.
As a method of solving these, Japanese Unexamined Patent Publication No. 2007-140046 (Patent Document 1) is proposed. This invention includes feeding means for drawing and feeding a long sheet material having a optical film serving as a member of an optical display device out from a roll on which the long sheet material is wound up, detecting means for detecting defects of the long sheet material that has been drawn out by the feeding means, cutting and processing means for cutting the long sheet material and processing the long sheet material into individual sheet materials based on the detection result by the detecting means, carrying means for carrying in order to perform a bonding process on the sheet material that has been cut and processed by the cutting and processing means, and bonding processing means for bonding the sheet material carried by the carrying means onto an optical display unit serving as a member of an optical display device, characterized in that these means are arranged on consecutive manufacturing line steps. According to the above configuration, the long sheet material having an optical film can be directly subjected to a cutting process into a desired size, and this cut sheet material can be bonded onto an optical display unit. Therefore, the long sheet material wound up onto a roll can be directly packaged and delivered, while conventionally a long sheet material is stamped and the stamped sheet material is packaged most carefully and delivered to an optical display device processing manufacturer.    Patent Document 1: Japanese Unexamined Patent Publication Laid-open No. 2007-140046